ES2674568T3 - Navigation control system for a robotic device - Google Patents

Abstract

A robotic cleaning device (100) comprising: a chassis (102) and an external frame (104) secured to the chassis (102) defining a structural cover of a height that facilitates the movement of the robotic cleaning device below the furniture; left and right sets of main drive wheels (112L, 112R) and respective independent electric motors (114L, 114R), mounted independently in combination with the chassis (102) that moves with the permitted pivot, for a pivoting movement with respect to this at opposite ends of the transverse diameter of the chassis (102), and which can be moved between a retracted position, subject to the weight of the robotic cleaning device (100) during operation, and an extended position, where its axes of rotation are below the lower plane of the chassis; a navigation control system (10) that operates so as to monitor the movement activity of the robotic cleaning device (100) within a defined work area, where the monitored movement activity includes at least one of a position history of the robotic cleaning device and an instantaneous position of the robotic cleaning device (100); and a transmission subsystem (12) that includes a laser transmitter, where the laser transmitter: is configured to redirect a transmission element of the laser transmitter; it is configured to cover the defined work area by transmitting a beam substantially parallel to a surface of the defined work area; and is integrated in combination with a raised point of a housing infrastructure of the robotic cleaning device (100), so that none of the structural characteristics of the robotic cleaning device (100) interferes with the operation of the transmission element of the laser transmitter , where the robotic cleaner further comprises a wheel drop sensor (124) integrated in combination with each of the main driving wheel assemblies (112L, 112R) and operating so as to generate a signal whenever any of the sets of Main drive wheels (112L, 112R) are in an extended position.

Description

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

DESCRIPTION

Navigation control system for a robotic device Background of the invention

(1) Field of the invention

The present invention relates in general to mobile robotic devices, and more in particular, to a navigation control system for a robotic device that operates under the direction of a navigation control algorithm that monitors the movement activity of the robotic device and uses the activity of movement to provide one or more control instructions to the robotic device, which, in response to this, implements an expected behavior, e.g. eg, one or more basic maneuvers and / or behavior patterns to increase the efficiency of coverage of said robotic devices to cover a defined work area, e.g. eg, sweeping, vacuuming in a room and / or performing maintenance of a residence yard.

(2) Description of related prior art

Robotic engineers have long worked on the development of an effective autonomous cleaning method. This has led to the development of two independent and distinct approaches for autonomous robotic devices: (1) deterministic cleaning; and (2) random cleaning.

In deterministic cleaning, where the cleaning rate is equal to the coverage rate and is, therefore, a more efficient cleaning method than random motion cleaning, the autonomous robotic device follows a defined path, e.g. eg, a bustrophedron path that is calculated to facilitate complete cleaning coverage of a given area while eliminating redundant cleaning. Deterministic cleaning requires the robotic device to have accurate knowledge of the position at all times, as well as its position history (where it has been), which, in turn, requires a sophisticated positioning system. An adequate positioning system, a positioning system with adequate precision for a deterministic cleaning could depend on scanning laser telemetry systems, ultrasonic transducers, a differential carrier phase GPS or other sophisticated methods, usually has an exorbitant cost and it requires a lot of labor, which requires a complicated previous configuration to accommodate the particular conditions of each area to be cleaned, e.g. eg, room geometry, furniture location. In addition, the methods that depend on the global positioning are rendered unusable by the failure of any part of the positioning system.

An illustrative example of a very sophisticated (and relatively expensive) robotic device for deterministic cleaning is the RoboScrub device manufactured by Denning Mobile Robotics and Windsor Industries. The RoboScrub device uses sonic and infrared detectors, shock sensors and a high precision laser navigation system to define the deterministic cleaning path. The navigation system used by the RoboScrub device requires the placement of numerous objects with large barcodes in various strategic positions within the area to be cleaned, and effective operation of the navigation system requires that at least four of said objects be visible so simultaneous. This accessibility requirement in practice limits the use of the RoboScrub device to clear open areas.

Other representative deterministic robotic devices are described in US Pat. UU. No. 5,650,072 (Azumi), 5,548,511 (Bancroft), 5,537,017 (Feiten et al.), 5,353,224 (Lee et al.), 4,700,427 (Knepper) and 4,119,900 ( Kreimnitz). These representative deterministic robotic devices have, similarly, a relatively high cost, require a previous configuration with a lot of labor and / or are limited in practice to large cleared areas of simple geometric configuration (square, rectangular rooms with little (or no) furniture).

Due to the limitations and difficulties inherent in purely deterministic cleaning systems, some robotic devices rely on pseudo-deterministic cleaning approaches, such as navigation by esteem. Navigation by estimation consists of continuously measuring the exact rotation of each driving wheel (e.g., using rotary optical encoders) to continuously calculate the position at that moment of the robotic device based on an initial point and orientation known. In addition to the disadvantages of having to start cleaning operations from a fixed position with the robotic device in a specific orientation, the driving wheels of robotic navigation devices by estimate are almost always subject to some degree of slippage, which leads to errors in the calculation of the actual position.

Consequently, robotic navigation devices by estimate are not generally considered reliable for cleaning operations of any prolonged duration, which results in system neglects that are difficult to solve, that is, areas of the surface to be cleaned that are not cleaned. . Other representative examples of pseudodeterminist robotic devices are described in US Pat. UU. No. 6,255,793 (Peless et al.) And 5,109,566 (Kobayashi et al.).

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

A robotic device that operates with a random movement, under the control of one or more random movement algorithms stored in the robotic device, represents the other basic approach to cleaning operations using autonomous robotic devices. The robotic device autonomously implements said random movement algorithm (s) in response to internal events, e.g. eg, signals generated by a sensor system, span of a period of time (random or predetermined). In a typical unobstructed room, a robotic device that operates under the control of a random movement algorithm will provide acceptable cleaning coverage with sufficient cleaning time. Compared to a robotic device that works with a deterministic cleaning mode, a robotic device that uses a random motion algorithm must work for a longer time period to achieve acceptable cleaning coverage.

To be assured that a robotic random movement device has cleaned 98% of an obstacle-free room, the robotic random movement device must work approximately five times more than a deterministic robotic device that has cleaning mechanisms for Similar size and it moves at approximately the same speed.

However, an area to be cleaned that includes one or more randomly placed obstacles causes a marked increase in runtime for a robotic random movement device to perform 98% of the cleaning coverage. Therefore, although the robotic random movement device is a relatively inexpensive means of cleaning a defined work area as opposed to a deterministic robotic device, the robotic random movement device requires a significantly longer cleaning time.

There is a need to provide a deterministic component to a robotic random movement device to improve its cleaning efficiency, in order to reduce the runtime for the robotic cleaning of random movement to achieve 98% cleaning coverage.

Published International Application No. WO 97/41451 discloses a proximity sensor system and an autonomous device, similar to a vacuum cleaner, which is provided with a pair of independent driving wheels. The device contains for guidance and proximity guidance a microprocessor system and a sonar system comprising at least one ultrasonic transmitter and one ultrasonic receiver. An additional mechanical touch sensor is also used in the form of a forward-facing bumper that contains the transmitter as well as the receiving microphone units.

Brief summary of the invention.

The present invention relates to a robotic cleaning device as presented in claim 1. Other embodiments are described in the dependent claims.

An object of the present invention is to provide a navigation control system that improves the cleaning efficiency of a robotic device by adding a deterministic component (in the form of a behavior prescribed by a navigation control algorithm) to the random movement of the generated robotic device. by the default behavior modes stored in the robotic device.

Another object of the present invention is to provide a navigation control unit that operates according to a navigation control algorithm, which includes a predetermined activation event that defines when the robotic device will implement the prescribed behavior.

Brief description of the drawings

A deeper understanding of the present invention and the associated features and advantages thereof can be made, referring to the following detailed description of the invention when considered in conjunction with the accompanying drawings, where:

Figure 1 is a schematic top view of a robotic device, by way of example, which has a particular utility when used in the navigation control system according to the present invention.

Figure 2 is a block diagram of the hardware, by way of example, for the robotic device of Figure 1.

Figure 3 is a schematic representation of a navigation control system that can be used with the present invention, comprising a transmission subsystem and a reception subsystem.

Figure 4 illustrates a polar division of a defined work area, in which a robotic device operates.

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

Figure 5A illustrates the operation of a preferred example of a transmission subsystem, which operates synchronously with the receiving subsystem of a preferred implementation of the navigation control system that can be used with the present invention.

Figure 5B illustrates the operation of the reception subsystem, which operates synchronously with the transmission subsystem of Figure 5A.

Figure 5C illustrates the operation of another example of a transmission subsystem, which operates synchronously with the receiving subsystem of a preferred example of the navigation control system that can be used in the present invention.

Figure 5D illustrates the operation of the reception subsystem, which operates synchronously with the transmission subsystem of Figure 5C.

Figure 6A illustrates a preferred example of a navigation control system, where the transmission subsystem is integrated in combination with the robotic device and the reception system functions as a base station mounted against a wall of a defined work area.

Figure 6B illustrates the set of transmission units, comprising the transmission subsystem of the robotic device of Figure 6A, and of the representative directed beams having predetermined emission patterns.

Figure 6C is a schematic illustration of a preferred example of the receiving subsystem of Figure 6A.

Figure 7 illustrates an example of a navigation control system, where the reception subsystem is integrated in combination with the robotic device and the transmission subsystem has a distributed configuration.

Detailed description of the invention

Referring now to the drawings, where the same reference numbers identify similar or corresponding elements in all different views, Figure 1 is a schematic top view of a preferred embodiment, by way of example, of a robotic device 100 having a particular utility in combination with a navigation control system 10. Figure 2 is a block diagram of the hardware of the robotic device 100 of Figure 1.

The hardware and behavior modes (coverage behavior for cleaning operations; escape behaviors for transient movement patterns; and safety behavior for emergency conditions) of robotic device 100, which iRobot Corporation of Burlington, MA, under the brand Commercial ROOMBA manufactures, distributes and / or markets, are briefly described in the following paragraphs to facilitate a deeper understanding of the navigation control system 10. In the non-provisional US patent application. UU. pending resolution and joint ownership with serial number 10 / 167,851, filed on June 12, 2002, entitled METHOD AND SYSTEM FOR MULTI-MODE COVERAGE FOR AN AUTONOMOUS ROBOT, and in the non-provisional US patent application. UU. Serial No. 10 / 320,729, filed on December 16, 2002, entitled AUTONOMOUS FLOOR-CLEANING DEVICE, provides additional details regarding the hardware and behavior modes of the robotic device 100.

In the following description of the robotic device 100, the use of the "forward" / "forward" terminology refers to the main (forward) direction of movement of the robotic device (see the arrow identified by the reference character "FM" in figure 1). The front / rear axle FAx of the robotic device 100 coincides with the average diameter of the robotic device 100 that divides the robotic device 100 into symmetrical left and right halves, which are defined as the dominant and non-dominant sides, respectively.

Robotic device

The robotic device 100 has a cylindrical housing infrastructure in general, which includes a chassis 102 and an external frame 104 fixed to the chassis 102, which defines a minimum height structural cover (to facilitate movement under the furniture). The hardware comprising the robotic device 100 can be classified as the functional elements of a power system, a drive system, a sensor system, a control module, a side brush assembly, or a self-adjusting cleaning head system , respectively, where all of them are integrated in combination with the housing infrastructure. In addition to said classified hardware, the robotic device 100 further includes a front bumper 106, which has a generally arched configuration, and a front wheel assembly 108.

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

The front bumper 106 (illustrated as a single component; alternatively, a two-segment component) is integrated in a mobile combination with the chassis 102 (by means of a pair of movable support elements) to extend outwardly from it. Whenever the robotic device 100 impacts with an obstacle (e.g., a wall, a piece of furniture) during its movement, the bumper 106 moves (compresses) towards the chassis 102 and returns to its extended (operational) position when the contact with the obstacle.

The front wheel assembly 108 is mounted in a shifted combination with respect to the chassis 102, so that the front wheel subset 108 is in a retracted position (due to the weight of the robotic device 100) during cleaning operations, where it is rotated freely on the surface to be cleaned. When the front wheel subassembly 108 encounters a fall during operation (e.g., stairs that descend, two-level floors), the front wheel assembly 108 moves to an extended position.

The power system hardware, which provides the power to power the electrically powered hardware of the robotic device 100, comprises a set of rechargeable batteries 110 (and associated lead wires, not shown) that is integrated in combination with the chassis 102

The drive system provides the means that propels the robotic device 100 and operates the cleaning mechanisms, e.g. eg, the side brush assembly and the self-adjusting cleaning head system, during the movement of the robotic device 100. The drive system comprises left and right sets of main drive wheels 112L, 112R, their independent electric motors 114L, 114R associated, and electric motors 116, 118 for the operation of the side brush assembly and the self-adjusting cleaning head subsystem, respectively.

The main drive wheel assemblies 112L, 112R are mounted independently in a shifted combination with respect to the chassis 102 (to have a pivotal movement with respect to this) at opposite ends of the transverse diameter (with respect to the front rear axle FAx) of the robotic device 100 and are in a retracted position (due to the weight of the robotic device 100) during operation, where the axes of rotation are approximately coplanar with the bottom of the chassis 102. If the robotic device 100 is removed from the surface it is clean, the main wheel assemblies 112L, 112R are pivoted to an extended position, where their geometric axes of rotation are below the lower plane of the chassis 102 (in this extended position the control module automatically disconnects the set of rechargeable batteries 110, which executes one of the safety behavior modes).

Electric motors 114L, 114R are mechanically coupled to the main drive wheel assemblies 112L, 112R, respectively, and operate independently by control signals generated by the control module in response to the implementation of a mode of behavior. The independent operation of the 114L, 114R electric motors allows the main wheel assemblies 112L, 112R to: (1) rotate at the same speed in the same direction to propel the robotic device 100 in a straight line, forward or backward ; (2) rotate in a differentiated manner (which includes the condition where a wheel assembly does not rotate) to effect a series of right and / or left turn patterns (over a whole spectrum of open or closed turns) of the robotic device 100; and (3) rotate at the same speed in opposite directions to make the robotic device 100 rotate on the site, that is, "rotate on itself", to provide an extensive repertoire of possibilities of movement to the robotic device 100.

The sensor system comprises a variety of different units with sensors that operate so as to generate signals that control the operations of the behavior modes of the robotic device 100. The described robotic device 100 includes obstacle detection units 120, detection units of slopes 122, wheel drop sensors 124, an obstacle tracking unit 126, an omnidirectional virtual wall detector 128, stop sensor units 130 and encoder units of the main wheels 132.

For the described embodiment, the obstacle detection units ("shocks") 120 are IR photoelectric cell sensors mounted in combination with the pairs of movable support elements of the front bumper 106. These detection units 120 operate so as to generate one or more signals indicating the relative displacement between one or more pairs of support elements whenever the robotic device 100 hits an obstacle, so that the front bumper 106 is compressed. The control module processes these signals to determine a point approximate contact with the obstacle, in relation to the front rear axle FAx of the robotic device 100 (and the mode (s) of behavior to be implemented).

The slope detection units 122 are mounted in combination with the front bumper 106. Each slope detection unit 122 comprises an IR emitter-detector pair configured and operating so as to establish a focal point such that that radiation emitted downward by the emitter it is reflected from the surface that it travels and is detected in the detector. If the detector does not detect the reflected radiation, that is, a fall is found, the uneven detection unit 122 transmits a signal to the control module (which causes one or more behavior modes to be implemented).

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

A wheel drop sensor 124, such as a contact switch, is integrated in combination with each of the main drive wheel assemblies 112L, 112R and the front wheel assembly 108, and operates so as to generate a signal whenever any of the wheel assemblies is in an extended position, that is, it is not in contact with the surface being traveled (which causes the control module to implement one or more behavior modes).

The obstacle tracking unit 126, for the described embodiment, is an IR emitter-detector pair mounted on the 'dominant' side (right side of Figure 1) of the robotic device 100. The emitter-detector pair is similar in configuration to the uneven detection units 112, but is positioned so that the emitter emits the radiation laterally from the dominant side of the robotic device 100. The unit 126 operates so that it transmits a signal to the control module whenever an obstacle is detected , as a result of radiation reflected from the obstacle and detected by the detector. The control module, in response to this signal, causes one or more behavior modes to be implemented.

A virtual wall detection system to be used in conjunction with the described embodiment of the robotic device 100 comprises an omnidirectional detector 128 mounted on the external frame 104 and an autonomous transmission unit (not shown) that transmits an axially directed confinement beam. The autonomous transmission unit is positioned so that the emitted confinement beam blocks an access path to a defined work area, thereby limiting the robotic device 100 to operations within the defined work area (e.g. , in an entrance to confine the robotic device 100 inside a specific room to be cleaned). Upon detection of the confinement beam, the omnidirectional detector 128 transmits a signal to the control module (which causes one or more modes of behavior to be implemented to move the robotic device 100 away from the confinement beam generated by the autonomous transmission unit).

A stop sensor unit 130 is integrated in combination with each electric motor 114L, 114R, 116, 118 and operates so that it transmits a signal to the control module when a change in the associated electric motor current is detected (which is indicative of a malfunction in the corresponding driven hardware). The control module operates in response to said signal to implement one or more modes of behavior.

An IR encoder unit 132 (see Figure 2) is integrated in combination with each main wheel assembly 112L, 112R, and operates so that it detects the rotation of the corresponding wheel and transmits signals corresponding thereto to the control module ( The wheel rotation can be used to provide an estimate of the distance traveled by the robotic device 100).

The control module comprises the microprocessing unit 135 illustrated in Figure 2, which includes I / O ports connected to the sensors and controllable hardware of the robotic device 100, a microcontroller and ROM and RAM memories. The I / O ports perform interface functions between the microcontroller and the sensor units and the controllable hardware, transferring signals generated by the sensor units to the microcontroller and transferring control signals (instructions) generated by the microcontroller to the controllable hardware to implement A specific mode of behavior.

The microcontroller operates so that it executes instruction sets to process the sensor signals, implement specific behavior modes, based on said processed signals, and generate control signals (instructions) for the controllable hardware based on the behavior modes implemented by the robotic device 100. The cleaning coverage and control programs for the robotic device 100 are stored in the ROM of the microprocessing unit 135, which includes the behavior modes, the sensor processing algorithms, the algorithms of generating control signals and a hierarchy algorithm to determine which mode or modes of behavior should be given control of the robotic device 100. The RAM of the microprocessing unit 135 is used to store the active state of the robotic device 100 , which includes the ID of the mode (s) of behavior according to those that robotic device 100 operates at that time and the hardware orders associated with them.

The side brush assembly 140 is configured and operated so as to drag particulate materials outside the periphery of the carcass infrastructure and direct said particulate materials towards the self-adjusting cleaning head system. The side brush assembly 140 provides the robotic device 100 with the ability to clean surfaces adjacent to motherboards, when the robotic device operates in a Obstacle Tracking behavior mode. As shown in Figure 1, the side brush assembly 140 is preferably mounted in combination with the chassis 102 in the front quadrant of the dominant side of the robotic device 100.

The self-adjusting cleaning head system 145, for the described robotic device 100, comprises a double stage brush assembly and a vacuum cleaner assembly, each of which is independently powered by an electric motor (reference number 118 in the Figure 1, actually identifies two independent electric motors, one for the brush set and one for the vacuum set). The capacity of

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

Cleaning of the robotic device 100 is typically characterized in terms of the width of the cleaning head system 145 (see reference character W in Figure 1).

The double stage brush assembly and the intake of the vacuum assembly are integrated in combination with a platform structure, which is mounted with the possibility of pivoting in combination with the chassis 102 and is operatively integrated with the brush assembly motor of double stage In response to a predetermined reduction in the rotation speed of the brush assembly motor, the brush assembly motor provides the driving force to swing the platform structure with respect to the chassis 102. The pivoting platform structure provides the ability to self-adjusting to the cleaning head assembly 145, which allows the robotic device 100 to easily transition between disparate surfaces during cleaning operations, e.g. eg, from carpeted surface to bare surface or vice versa, without suspending execution.

The double stage brush assembly comprises asymmetric reverse rotation brushes that are located (in front of the inlet of the vacuum assembly), configured and operated so as to direct the waste of particulate material into a removable dust cartridge (not it shows). The positioning, configuration and operation of the brush assembly simultaneously direct the waste of particulate material towards the entrance of the vacuum assembly, so that, as a result of the movement of the robotic device 100, the vacuum assembly can subsequently ingest the particles that The double stage brush set does not sweep.

The operation of the vacuum assembly independently of the self-adjusting brush assembly allows the vacuum assembly to generate and maintain a greater suction force using a battery power source, which would be possible if the vacuum assembly functioned depending on the brush assembly.

Modes of behavior of the robotic device

The robotic device 100 uses various behavior modes to efficiently clean a defined work area, where the behavior modes are layers of control systems that can operate in parallel. The microprocessing unit 135 operates so as to execute a prioritized arbitration approach to identify and implement one or more dominant modes of behavior for any given scenario based on the inputs from the sensor system.

The behavior modes for the robotic device 100 described can be characterized as: (1) coverage behavior modes; (2) escape behavior modes; and (3) modes of safety behavior. The coverage behavior modes are primarily designed to allow the robotic device 100 to carry out its cleaning operations in an efficient and effective manner, and the escape and safety behavior modes are priority behavior modes implemented when a signal from the sensor system indicates an alteration in the normal operation of robotic device 100, p. eg, encounters an obstacle, or is likely to be altered, e.g. eg, a fall detected.

Representative and illustrative coverage (cleaning) behavior modes of robotic device 100 include: (1) a Localized Coverage pattern; (2) a pattern of Obstacle Tracking Coverage (or Edge Cleaning), and (3) a Room Coverage pattern. The Localized Coverage pattern causes robotic device 100 to clean a limited area within the defined work area, e.g. eg, an intensive transit area. In a preferred example, the Localized Coverage pattern is implemented by means of a spiral algorithm (although other types of algorithms can be used for delimited areas, e.g. polygonal). The spiral algorithm, which causes the spiraling outward or spiraling movement inside the robotic device 100 is implemented by control signals from the microprocessing unit 135 to the main wheel assemblies 112L, 112R to change its radius (s) / turning radii as a function of time (thereby increasing / decreasing the spiral movement pattern of robotic device 100).

The robotic device 100 operates in the Localized Coverage pattern for a predetermined or random period of time, at a predetermined or random distance (e.g., a maximum spiral distance) and / or until a specific event occurs, e.g. . eg, the activation of one or more of the obstacle detection units 120 (collectively a transition condition). Once a transition condition occurs, the robotic device 100 can implement or transition to a different mode of behavior, e.g. eg, a Straight Line behavior mode (in a preferred example of the robotic device 100, the Straight Line behavior mode is a low priority default behavior that propels the robot in an approximately straight line at a preset speed of approximately 0.306 m / s) or a Bounce behavior mode in combination with a Straight Line behavior mode.

If the transition condition is the result of the robotic device 100 encountering an obstacle, the robotic device 100 may take other actions instead of transitioning to a different mode of behavior. The robotic device 100 may momentarily implement a mode of behavior to avoid the obstacle or escape from it and resume operation under the control of the spiral algorithm (i.e., continue to describe a spiral in the same direction). As an alternative, robotic device 100 can implement

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

momentarily a mode of behavior to avoid the obstacle or escape from it and resume its operation under the control of the spiral algorithm (but in the opposite direction, reflected spiral).

The Obstacle Tracking Coverage pattern causes robotic device 100 to clean the perimeter of the defined work area, e.g. eg, a room delimited by walls, and / or the perimeter of an obstacle (eg, furniture) within the defined work area. Preferably, the robotic device 100 uses an obstacle tracking unit 126 to maintain its position continuously with respect to an obstacle, e.g. eg, a wall, a piece of furniture, so that the movement of the robotic device 100 causes it to move adjacently, and simultaneously clean, along the perimeter of the obstacle. Different implementations of the obstacle tracking unit 126 can be used to implement the Obstacle Tracking behavior pattern.

In a first example, the obstacle tracking unit 126 operates so as to detect the presence or absence of the obstacle. In an alternative example, the obstacle tracking unit 126 operates so as to detect an obstacle and then maintain a predetermined distance between the obstacle and the robotic device 100. In the first example, the microprocessing unit 135 operates, in response to the signals from the obstacle tracking unit, so that it implements small CW (clockwise) or CCW (counterclockwise) turns to maintain its position with respect to the obstacle. The robotic device 100 implements a small CW turn when the robotic device 100 performs the transition from obstacle detection to non-detection (from reflection to non-reflection) or to implement a small CCW turn, when the robotic device 100 performs the non-detection transition to detection (from non reflection to reflection). The robotic device 100 implements similar turning behaviors to maintain the predetermined distance from the obstacle.

The robotic device 100 operates in the Obstacle Tracking behavior mode for a predetermined or random period of time, at a predetermined or random distance (e.g., a maximum or minimum distance) and / or until an event occurs specific, p. eg, the activation of one or more of the obstacle detection units 120 a predetermined number of times (collectively a transition condition). In a certain example, the microprocessor 135 will cause the robotic device to implement an Alignment behavior mode upon activation of the obstacle detection units 120 in the Obstacle Tracking behavior mode, where it implements a CCW rotation of minimum angle to align the robotic device 100 with the obstacle.

The robotic device 100 may use the Room Coverage pattern to clean any defined work area that is delimited by walls, stairs, obstacles or other barriers (e.g., a virtual wall unit). A preferred example of the Room Coverage pattern comprises the Random Bounce behavior mode in combination with the Straight Line behavior mode. Initially, the robotic device 100 moves under the control of the Straight Line behavior mode, that is, a straight line algorithm (the main drive wheel assemblies 112L, 112R operate at the same rotation speed in the same direction) until He encounters an obstacle. Upon activation of one or more of the obstacle detection units 120, the microprocessing unit 135 operates so that it calculates an acceptable range of new addresses based on the obstacle detection unit (s) 126 activated ( s). The microprocessing unit 135 selects a new orientation within the acceptable range and implements a CW or CCW turn to achieve the new orientation with minimal movement. In some examples, the orientation of the new turn may be followed by a forward movement to increase the cleaning efficiency of the robotic device 100. The new orientation may be selected randomly over the entire acceptable range of orientations, or depending on some statistical approach to selection, p. eg, Gaussian distribution. In other examples of Room Coverage behavior mode, microprocessing unit 135 can be programmed to change orientations randomly or at predetermined instants, without input from the sensor system.

The robotic device 100 operates in the Room Coverage behavior mode for a predetermined or random period of time, at a predetermined or random distance (e.g., a maximum or minimum distance) and / or until an event occurs specific, p. eg, the activation of obstacle detection units 120 a predetermined number of times (collectively a transition condition).

A preferred implementation of the robotic device 100 includes four escape behavior modes: a Spin behavior mode, a Edge behavior mode, a Wheel Fall behavior mode, and a Slow behavior behavior mode. Someone skilled in the art will appreciate that the robotic device 100 can use other modes of behavior. One or more of these modes of behavior can be implemented, for example, in response to an increase in the current in one of the electric motors 116, 118 of the side brush assembly 140 or that the double stage brush assembly is above of a high or low stop threshold, the front bumper 106 is in a compressed position for a certain period of time, the detection of a wheel fall event.

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

In the Spinning behavior mode, the robotic device 100 rotates at the site in a random direction, starting at a higher speed (e.g., twice the normal turning speed) and decreasing to a lower speed (half of normal spin speed), that is, small panic spins and large panic spins, respectively. The small panic spins are preferably in the range of 45 ° to 90 °, the large panic spins are preferably in the range of 90 ° to 270 °. Turning mode prevents the robotic device 100 from getting stuck in obstacles in the room, e.g. eg, a high place on the carpet, a slanted lamp base, gets stuck under obstacles in the room, e.g. eg, under a sofa or being trapped in a confined area.

In the Edge behavior mode, the edge of an obstacle is followed until a predetermined number of degrees has been rotated, e.g. eg, 60 °, without activating any of the obstacle detection units 120, or until the robotic device has rotated a predetermined number of degrees, e.g. eg 170 °, from the beginning of the Edge behavior mode. The Edge behavior mode allows robotic device 100 to move through the smallest possible openings to escape from confined areas.

In the Wheel Drop behavior mode, the microprocessor 135 reverses the direction of the main drive wheel assemblies 112L, 112R momentarily, then stops them. If the activated wheel drop sensor 124 is deactivated within a predetermined period of time, the microprocessor 135 then re-implements the mode of behavior that was being executed before the activation of the wheel drop sensor 124.

In response to certain events, p. For example, the activation of a wheel drop sensor 124 or an unevenness detector 122, the Slowdown behavior mode is implemented to decrease the speed of the robotic device 100 over a predetermined distance and then increase it again until its normal operating speed.

When the sensor subsystem detects a security situation, p. For example, a series of brush stops or wheels that cause the corresponding electric motors to be temporarily deactivated, the activation of a wheel drop sensor 124 or a slope detection sensor 122 for a period of time greater than the default, the robotic device 100 is brought to a shutdown state. In addition, it can generate an audible alarm.

The above description of the modes of behavior of the robotic device 100 is intended to be representative of the types of modes of operation that can be implemented by the robotic device 100. Someone skilled in the art will appreciate that the modes of behavior described above can be implemented in others. combinations and / or circumstances.

Navigation control system

Figure 3 is a schematic representation of a navigation control system 10 for use in combination with a robotic device 100, in order to improve its cleaning efficiency by adding a deterministic component (in the form of a control signal that controls remote movement of the robotic device 100) to the movement algorithms, which includes random movement, implemented autonomously by the robotic device 100. The navigation control system 10 comprises a transmission subsystem 12 and a reception subsystem 20 that operate according to the direction of a navigation control algorithm. The navigation control algorithm includes a definition of a predetermined activation event. The specific characteristics and properties of the transmission subsystem 12 and the reception subsystem 20 depend on whether the particular subsystem is integrated in combination with the robotic device 100, or operates as a "base station" for the navigation control system 10.

Described, roughly, the navigation control system 10 operates, according to the direction of the navigation control algorithm, so as to monitor the movement activity of the robotic device 100 within the defined work area. In a preferred example, the monitored motion activity is defined in terms of the "position history" of the robotic device 100, as described in greater detail below. In another example, the monitored motion activity is defined in terms of the "instantaneous position" of the robotic device 100, as defined in greater detail below.

The predetermined activation event is a specific occurrence or condition in the movement activity of the robotic device 100. After the predetermined activation event occurs, the navigation control system 10 operates so as to generate and communicate a control signal. to the robotic device 100. In response to the control signal, the robotic device 100 operates so that it implements or executes a behavior prescribed by the control signal, that is, the prescribed behavior. This prescribed behavior represents a deterministic component of the movement activity of the robotic device 100.

In the preferred example of the navigation control system 10 based on the position history, the system 10 is configured and operated so as to create a "division" of any defined work area, where the device

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

robotic 100 should operate, p. eg, a room to clean. Division is used herein in the sense that the defined work area is segmented into a set of individual cells, which may or may not be the same size. For example, Figure 4 illustrates, by way of example, the polar division of a defined work area into a set of individual cells C (the reference characters BSt identify the "base station") of unequal sizes. The position of each cell C (in terms of its center) is identified in terms of the polar coordinates (r, 0), referenced to the base station BSt as the origin (0, 0). A crosslinked map of the cells C comprising the defined work area is stored in the memory of the navigation control system 10. Someone skilled in the art will appreciate that the navigation control system 10 can use other coordinate systems, e.g. eg, a Cartesian plane coordinate system, to define the position of individual cells C within the predetermined work area.

Preferably, the navigation control system 10 operates so as to define the size of the individual cells C, so that the length and width dimensions of an individual cell C are not greater than one half of the width (W) of the system of cleaning head 145 of robotic device 100 (see Figure 1 and the corresponding previous analysis).

The navigation control system 10 operates so as to generate a position history of the robotic device 100 within the defined work area in terms of said individual cells C (in order to minimize the memory requirements for the storage of the position history ). The position history comprises a set of instantaneous and discrete positions (in terms of individual cells C) of the robotic device 100 over a time interval, where the time interval is a variable that depends on the "activation condition" of the navigation control algorithm implemented by the navigation control system 10.

Each instantaneous and discrete position of the robotic device 100 is determined by operating the transmission subsystem 12 that transmits a set of directional beams and operating the reception subsystem 20 so that it detects one or more of said directional beams and processes a signal parameter of ( of the (s) detected to determine an absolute heading parameter and a distance parameter, between the transmission subsystem 12 and the reception subsystem 20 in an instant of time. Each pair of heading and distance parameters establishes an instantaneous and discrete position of the robotic device 100. For the preferred 'position history' example, the navigation control system 10 operates so that it correlates each instantaneous and discrete position with a cell. individual C of the crosslinked map. A set of heading and position pairs, that is, a set of instantaneous positions during a time interval defines a set of cells C, which are identified in the receiving subsystem 20 as the position history of the robotic device 100 for the interval of time.

In a preferred example of the navigation control system 10 based on the instantaneous position, the system 10 processes each instantaneous and discrete position as established, in accordance with the control of the navigation control algorithm, to determine whether said instantaneous and discrete position is the default activation event defined by the navigation control algorithm.

In an advanced example of the navigation control system 10, the system 10 is further configured and operated so as to determine a translation vector (indicating the direction of movement of the robotic device 100 within an individual cell C or in the instantaneous and discrete position) at each instant of time. These translation vectors can be stored in memory together with the corresponding C cells as a component of the position history of the robotic device 100.

The navigation control system 10 also operates, in accordance with the direction of the navigation control algorithm, so that it generates and communicates a control signal to the robotic device 100, provided that the navigation control system 100 carries out the event default activation. In response to any of said control signals, the robotic device 100 is configured and operated so as to initiate a prescribed behavior. The prescribed behavior comprises the deterministic component added to the movement activity of the random movement of the robotic device 100 by means of the navigation control system 10.

In a possible implementation of the invention, the prescribed behavior of the robotic device 100 comprises one or more basic maneuvers, such as CW and CCW turns, forward or backward movement, speed decrease, speed increase and stop. The CW and / or CCW turns can be implemented using the rotation techniques of the robotic device 100 described above, and the rotation angles can be, for example, over a 360 ° spectrum at predetermined intervals, e.g. eg, 5th or 10th. Alternatively, or in addition, the CW and / or CCW turns can be up to a specific azimuthal orientation (referenced to the base station as the origin) where the navigation control system 10 is configured and operated so that the translation vector is A variable that can be determined. Of these basic maneuvers, forward movement (in a straight line) is usually the maneuver to which the robotic device 100 automatically returns (implements) by default once one or more of the other basic maneuvers have been completed.

In another possible implementation of the invention, the prescribed behavior of the robotic device 100 comprises one or more of the modes of behavior described herein. In another possible implementation of the invention,

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

The prescribed behavior of the robotic device 100 comprises a combination of the basic maneuvers and the modes of behavior described herein.

The transmission subsystem 12 operates so that it transmits a number of directed beams that have a predetermined emission pattern along a specific propagation axis. Preferably, the directed beams are flat, that is, substantially parallel to the surface of the defined work area.

In preferred examples of the navigation control system 10, the transmission subsystem 12 is integrated in combination with the robotic device 100. The transmission subsystem 12 is configured and operated so as to functionally emulate an omnidirectional transmission source with respect to the area of defined work, that is, emitting a plurality of directed beams covering the defined work area. For these preferred implementations, the robotic device 100 further includes a reception unit 16 (see Figure 3) that is configured and operated so that it receives control signals from the reception subsystem 20 (see the analysis below concerning the unit transmission 32 of the reception subsystem 20). Although the receiving unit 16 is represented as a dedicated receiving unit for the control signals, it is preferable that the omnidirectional detector 128 (of the virtual wall detection system) described above is adapted to detect and process said control signals.

In a preferred example, the transmission subsystem 12 comprises a conventional mechanical sweep transmitter, e.g. eg, a laser, which is integrated in combination with a raised point of the housing infrastructure of the robotic device 100, so that none of the structural characteristics of the robotic device 100 interfere with its operation. The mechanical scan transmitter is configured and operated so as to emit the plurality of directed beams while simultaneously redirecting (mechanical scanning) the transmission element so that each directed beam has a different propagation axis. Next, other characteristics and properties of the mechanical scan transmitter are described in terms of individual transmission units 14n for a simpler description.

Another preferred example of the transmission subsystem 12 comprises a set of transmission units 14n, where N is an integer that defines the number of individual transmission units comprising the set for the navigation control system 10, which are integrated in combination with the robotic device 100 on the entire periphery of its housing infrastructure. Each transmission unit 14n is configured and operated so that it emits a directed beam with a predetermined emission pattern along a specific propagation axis. Preferably, the transmission subsystem 12 is configured and operated so that the directed beams emitted are flat.

In a basic example of the transmission subsystem 12, the transmission units 14n are fungible / interchangeable, where each operates so as to emit a beam directed at a common operating frequency. Preferably, the common operating frequency of the transmission units 14n is in the infrared range, that is, between about 750 nm and about 1.4 x 104 nm, preferably between 880 nm and about 980 nm, although someone skilled in the art will appreciate that other wavelengths can be used, e.g. eg, in the range of radio frequencies, in the range of microwave frequencies, when implementing the navigation control system 10.

Preferably, the directed beams of common operating frequency emitted by the transmission units 14n are periodically modulated, e.g. for example, at 10 KHz for 50 ms and deactivated for 300 ms. The modulation of the directed beams facilitates its detection by the reception subsystem 20, that is, the reception subsystem 20 can easily discriminate between the modulated directed beams emitted by the transmission subsystem 12 and any other sources of electromagnetic radiation that may be active in the defined work area, p. eg, television remote control units, wireless computer keyboards, microwaves, ambient radiation, such as sunlight. For the basic example, it is also preferred that the transmission units 14n operate sequentially so that any transmission unit 14n is activated by cycles for a predetermined period of time and then deactivated by cycles, then activated by cycles. next transmission unit 14n (adjacent) for the predetermined period of time and is deactivated by cycles, etc. Operating the transmission subsystem 12 in the above manner, that is, modulation of the directed beam, sequentially activating / deactivating the transmission units 14n, minimizes the power requirements of the transmission subsystem 12 and reduces parasitic noise / collateral energy that could negatively impact the operation of the navigation control system 10.

Ordinarily, a navigation control system 10 using the basic example of the transmission subsystem 12, that is, all transmission units 14n interchangeably emit beams directed at a common operating frequency, cannot be used to determine the translation vectors of the robotic device 100 because the reception subsystem 20 cannot differentiate between the directed beams emitted by the transmission units 14n and therefore cannot identify any particular transmission unit 14n. However, the inventors have developed two innovative ways of transmitting and processing directed beams emitted by a transmission subsystem 12 comprising interchangeable transmission units 14n, so that the

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

Receive subsystem 20 can individually identify an interchangeable transmission unit 14n, and, based on said identification, establish a translation vector for robotic device 100.

Consequently, in an improved version of the basic example of the transmission subsystem 12, the interchangeable transmission units 14n operate in a predetermined manner that allows the reception subsystem 20 to process the detected directed beams to identify the directed beam having the intensity of maximum signal, which in turn allows the reception subsystem 20 to identify the interchangeable transmission unit 14n that emitted said directed beam. This in turn allows the reception subsystem 20 to determine the orientation and, therefore, the translation vector of the robotic device 100.

Referring to FIG. 5A, the transmission subsystem 12 is first activated in cycles so that all transmission units 14n emit directed beams during a predetermined synchronization period, as identified by the reference character tSY, since then it is deactivated by cycles. The reception subsystem 20 operates so that it detects and processes one or more directed beams emitted by the transmission units 14n and identifies the predetermined synchronization period tSY of the transmission subsystem 12. This identification allows the reception subsystem 20 to synchronize the operations between the transmission subsystem 12 and the reception subsystem 20 upon initializing a timed sequence at the end of the predetermined synchronization period tSY (the reference character tü identifies the start of the timed sequence in Figure 5A).

The transmission subsystem 12 also operates so that the individual transmission unit 14n is activated and deactivated in cycles sequentially at predetermined moments with respect to the start of the t0 timed sequence established by the reception subsystem 20. For example, with respect to FIG. 5A, illustrating a transmission subsystem 12 comprising four transmission units 14n (arbitrarily identified as the first transmission unit 141, the second transmission unit 142, the third transmission unit 143 and the fourth unit of transmission). transmission 144), where the transmission subsystem 12 is configured and operated so that each of the transmission units 141, 142, 143, 144 is cycled sequentially to emit a directed beam that makes the transition of an intensity zero signal (0), at maximum signal strength, at zero signal strength (0), and then deactivated per cycle s (Figure 5A illustrates, by way of example, a sawtooth transition pattern, someone skilled in the art will appreciate that other signal strength transition patterns can be used when implementing the invention described herein, e.g. eg, a ramp signal strength).

That is, the first transmission unit 141 is activated by cycles and transitions to a maximum signal intensity at time t1. The second transmission unit 142 is activated by cycles when the directed beam of the first transmission unit 141 reaches its maximum signal intensity at time t1. The second transmission unit 142 transitions to a maximum signal intensity at time t2, at which time the first transmission unit 141 has made the transition to a zero signal intensity (0) and is deactivated by cycles. The third transmission unit 143 is activated by cycles when the directed beam of the second transmission unit 142 reaches its maximum signal intensity at time t2. The above operating pattern is repeated for the second, third and fourth transmission unit 142, 143, 144, as appropriate, so that at time t3 the second transmission unit 142, the directed beam emitted by the third, is deactivated by cycles. Transmission unit 143 has reached its maximum signal strength, and the fourth transmission unit 144 is activated by cycles; and at time t4 the third transmission unit 143 is deactivated by cycles and the directed beam emitted by the fourth transmission unit 144 has reached its maximum intensity. The transmission subsystem 12 operates in a manner that repeats the synchronization and sequential transmission procedure described above during operation of the navigation control system 10.

In another improved version of the basic example of the transmission subsystem 12, the interchangeable transmission units 14n operate in a different predetermined manner that allows the receiving subsystem 20 to process the detected directed beams to identify the directed beam having the maximum signal intensity , which in turn allows the reception subsystem 20 to identify the interchangeable transmission unit 14n that emitted said directed beam. This in turn allows the reception subsystem 20 to determine the orientation and, therefore, the translation vector of the robotic device 100.

Referring to Fig. 5C, the transmission subsystem 12 is first activated in cycles so that all transmission units 14n emit directed beams during a predetermined synchronization period, as identified by the reference character t12, since then it is deactivated by cycles. The receiving subsystem 20 operates so that it detects and processes one or more directed beams emitted by the transmission units 14n and identifies the predetermined synchronization period t12 of the transmission subsystem 12. This identification allows the reception subsystem 20 to synchronize the operations between the transmission subsystem 12 and the reception subsystem 20 upon initializing a timed sequence at the end of the predetermined synchronization period tSY (the reference character t0 identifies the start of the timed sequence in Figure 5A).

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

The transmission subsystem 12 also operates so that the individual transmission unit 14n is activated and deactivated in cycles sequentially at predetermined moments with respect to the start of the t0 timed sequence established by the reception subsystem 20. For example, with respect to Figure 5C, illustrating a transmission subsystem 12 comprising four transmission units 14n (arbitrarily identified as the first transmission unit 141, the second transmission unit 142, the third transmission unit 143 and the fourth unit of transmission). transmission 144), where the transmission subsystem 12 is configured and operated so that each of the transmission units 141, 142, 143, 144 is activated sequentially to emit a pulsed directed beam with a predetermined pulse width P1, P2, P3, P4, respectively, with a predetermined signal strength, and then deactivated by cycles.

That is, the first transmission unit 141 is activated by cycles in your (where the first "1" identifies the transmission unit number and the second "1" indicates that the transmission unit is active by cycles) and is deactivated by cycles in t12 (where "2" indicates that the transmission unit is deactivated by cycles). Similarly, the second transmission unit 142 is activated by cycles at t21 and deactivated by cycles at t22, the third transmission unit 143 is activated by cycles at t31 and deactivated by cycles at t32 and the fourth transmission unit 144 is activated by cycles in t41 and deactivated by cycles in t42. The transmission subsystem 12 operates in a manner that repeats the synchronization and sequential transmission procedure described above during operation of the navigation control system 10.

In a more sophisticated example of the transmission subsystem 12, the transmission units 14n are discrete and identifiable, where each transmission unit 14n operates at a single operating frequency to emit a directed beam (which is preferably flat with respect to the surface of the defined work area) that has a predetermined emission pattern along a specific propagation axis. Preferably, these operating frequencies are also modulated to facilitate their detection by the reception subsystem 20 in an environment where other sources of electromagnetic radiation operate. Since each directed beam can be easily and uniquely identified, the receiving subsystem 20 can process the directed beams detected in a conventional manner to obtain not only the absolute course of the robotic device 100, but also the translation vector of the robotic device 10 at any particular moment.

The receiving subsystem 20 of the navigation control system 10 comprises a processing unit 22 that includes a microprocessor 24, a signal processing unit 26, a memory module 28 and a set of detection units 30m. Additionally, the reception subsystem 20 may also include a transmission unit 32 for those examples of navigation control system 10 where the reception subsystem 20 operates or functions as the base station for the navigation control system 10.

Memory module 28 comprises RAM 28A and ROM 28B. The data related to the ongoing operation of the robotic device 100 within the defined work area is stored in RAM 28A. Said operational data in progress may include the crosslinked map of cells C, which define the defined work area, and the position history of the robotic device 100, within the work area defined for the realization of the 'position history' of the system of navigation control 10. Stored in ROM 28B there is one or more navigation control algorithms for the navigation control system 10, a set of one or more control signals associated with each navigation control algorithm and a processing algorithm. of signals to convert signals generated by the signal processing unit 26 into one or more sets of instantaneous position parameters, that is, a heading, distance (and translation vector if applicable). For the example of the ‘position history’ of the system 10, a set of instantaneous position parameters that define the position history of the robotic device 100, which are correlated with the crosslinked map to identify the cells C comprising the position history.

The term "navigation control algorithm" as used herein encompasses a set of instructions that: (a) define how the navigation control system 10 uses position history or instantaneous position (eg, count and compare visited cells, a true or false determination of the visited cells, true or false determination if the default activation event has occurred); (b) defines the event or activation events associated with the use of position history or instantaneous position; and (c) identifies the control signal (s) to be implemented when the activation event occurs. For example, in a representative navigation control algorithm for the example of the 'position history' of the navigation control system 10 that can be used in combination with the present invention, the microprocessor 24 operates so that it counts and stores the number of visits to each cell and calculate the total number of visits to adjacent cells (neighbors) to each of said visited cells (cell count). The microprocessor 24 also operates so that it compares the total number of visits to neighboring cells, while visiting each cell, with a threshold value (see, eg, Figure 4 where "Cv" identifies a visited cell and "Cc "identifies the eight (8) cells adjacent to the visited cell Cv). If the total number of visits to neighbors (e.g., fifteen (15) in the example in Figure 4) for any visited cell is below the threshold value (the activation event), the microprocessor 24 operates so that a control signal is communicated to the robotic device 100. The control signal causes the robotic device 100 to implement one or more behavior modes specified by the control signal, e.g. eg, a Localized Coverage pattern, as described above.

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

In another representative navigation control algorithm for the 'position history' example of the navigation control system 10, one or more cells are previously identified in the stored crosslinked map (ie, before operating the robotic device 100) as "critical points" in the defined work area. While the robotic device 100 visits any particular cell C, the microprocessor 24 operates so as to determine if the visited cell has been identified as a "critical point" (determination of true or false). If the microprocessor 24 determines that the visited cell C is a "critical point" (activation event), the microprocessor 24 operates so that a control signal is communicated to the robotic device 100 via the control signal transmission unit 32. The reception of the control signal causes the robotic device 100 to implement the prescribed behavior specified by the control signal, e.g. eg, one or more of the basic maneuvers described above and / or a Localized Coverage pattern or a mode of Obstacle Tracking behavior, as described above.

The above representative examples of navigation control algorithms for the 'position history' example of the navigation control system 10 are implemented without knowledge of the translation vector of the robotic device 100, that is, based solely on the identification of the cells visited by means of the heading and distance parameters obtained by the reception subsystem 20. Another representative example of a navigation control algorithm for the example of the 'position history' of the navigation control system 10 uses the vector of translation as an element of position history when sending a control signal.

The microprocessor 24 operates so that it counts and stores the number of times a cell has been visited (cell count) and also operates so that it compares this number with the number of times each adjacent (or neighboring) cell has been visited. . For this navigation control algorithm, the activation event is a numerical difference between the number of visits to the cell visited at that time and the number of visits to each of the neighboring cells, which identifies the cell or neighboring cells that They have been the least visited compared to the cell visited at that time. The activation event would cause the reception system 20 to send a control signal to the robotic device 100 that would move the robotic device 100 from the cell visited at that time to the neighboring cell that has been the least visited, e.g. eg, by implementing one or more basic maneuvers, as described herein. If two or more neighboring cells have been the least visited, the control signal would cause the robotic device to move from the cell visited at that time to the less visited neighboring cell that is the most compatible with the translation vector of that moment of the robotic device 100, p. eg, minimum translation distance.

Using Figure 4 as an example, where "Cv" identifies the cell visited at that time and "Cc" identifies the eight (8) cells adjacent, or neighboring, to the cell visited at that time Cv, the neighboring cells Cc that they have been visited only once are the Cc neighboring cells less visited. If the translation vector at that time of the robotic device 100 is indicated by the reference characters TV, the control signal would cause the robotic device 100 to continue moving in a straight line, that is, the robotic device 100 would execute the basic maneuver of forward movement (or Straight Line behavior mode) (if robotic device 100 was currently operating in some other behavior mode).

A representative navigation control algorithm for the 'instantaneous position' of the navigation control system 10 uses a time span (both random and predetermined) as the default activation event to cause the robotic device 10 to move to a predetermined position B in the defined work environment. The microprocessor 24 operates, after the end of the time span (the predetermined activation event), so as to determine the instantaneous position (hereinafter identified as "position A") of the robotic device 100, as described herein. Since position A is an unknown variable until the predetermined activation event occurs, the prescribed behavior, that is, the basic maneuvers necessary to move the robotic device 100 from position A to position B are also unknown. Once the navigation control system 10 has determined position A, the basic maneuvers necessary to move the robotic device 100 from position A to position B can be determined, since both position A and position B are variable known (in terms of their heading pairs, known distance parameters with respect to the reception subsystem 20). A determination of the basic maneuvers that the robotic device 100 will implement by any conventional computational technique can be achieved.

Another navigation control algorithm, by way of example, for the example of 'instantaneous position' of the navigation control system 10 is a variation of the navigation control algorithm of 'critical point' for the example of 'position history' of the navigation control system 10. In this illustrative example, both position A and position B are known variables and, consequently, the basic maneuver (s) to move the robotic device 100 from the position A to position B are known. In this example, the default activation event is a TRUE determination that the instantaneous position of robotic device 100 is equal to position A (position A can be stored in memory 28 as a "zone" that defines a certain arbitrary centered area around position A, instead of a point position, to increase the probability that the instantaneous position of the robotic device 100, at a certain time, is equal to position A).

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

The reception subsystem 20 comprises a set of detection units 30m, where M is an integer that defines the number of individual detection units comprising the set for the navigation control system 10. The number and positioning of the set of units of 30m detection should be such that as much as possible of the defined work area is within the field of view of the receiving subsystem 20, and that the field of vision of at least two (although preferably more) detection units 30m covers the same area within the defined work area.

In preferred examples of the navigation control system 10, the reception subsystem 20 functions as a "base station" for the system 10. In this functional role, the reception subsystem 20 is a standalone and portable unit that is stationary placed inside of the defined work area, preferably in contact with a wall that delimits the defined work area (the 'wall unit' configuration). Alternatively, the reception subsystem 20 can be located within the defined work area distally with respect to the walls that delimit the defined work area (the ‘independent’ configuration). The reception subsystem 20, as the base station, establishes and, for the example of 'position history' of the navigation control system 10, stores the reticulated map of cells representing the defined work area and representing the origin (0 , 0) of the crosslinked cell map described above.

For those examples where the reception subsystem 20 operates with a wall unit configuration, the individual detection units 30m have a known separation ratio and are configured and operated so that they have a 180 ° field of view. For example, Figure 2 illustrates an example of the reception subsystem 20 comprising two detection units 30m (M = 2) separated by a known angular distance "9". Figure 6C illustrates another example of the reception subsystem 20, comprising three detection units 30m (M = 3), that is, 3012, 3023, 3013, which have known angular separations identified by "912", "923", and "913", respectively. Some preferred examples of the wall unit configuration of the navigation control system 10 include three detection units 30m to provide absolute heading data to the robotic device 100. A minimum of two detection units 30m is required to provide the signal information required for the reception subsystem 20. More than three 30m detection units can be used to increase the resolution of the reception subsystem 20, but at an additional cost for each additional 30m detection unit and associated signal processing circuits (see Figure 6C illustrating representative signal processing circuits associated with a detection unit 30m).

For those examples where the reception subsystem 20 operates with an independent configuration, the individual detection units 30m, similarly, are separated by known angular distances and are configured and operated so that they have a field of view greater than 180 ° . A representative example of the reception subsystem 20 operated as an independent base station would comprise four detection units 30m.

The detection units 30m are configured and operated so that they detect a parameter of one or more of the directed beams emitted by the transmission units 14n, p. eg, the voltages V representing the relative signal intensities of the directed beam (beams) detected (s). In a preferred example, each detection unit 30m is configured and operated so that it averages the detected signal strength parameter (e.g., voltage) when the detection unit 30m detects two simultaneously directed beams. The reception subsystem 20 executes a signal processing algorithm that processes the detected parameters provided by the detection units 30m, that is, relative signal intensities of the detected beams, which uses a conventional technique to determine the absolute heading between the device robotic 100 and the reception subsystem 20.

To provide the ability to determine the distance to the reception subsystem 20, preferably, the reception subsystem 20 is calibrated before use. This entails placing the robotic device 100 at a predetermined distance from the reception subsystem 20 and operating one (or more) of the transmission units 14n to emit a beam directed to the reception subsystem 20. The parameter of the directed beam detected by the units 30m detection, p. For example, a voltage representing the signal intensity of the directed beam as detected is correlated with the predetermined distance and is used to generate a table of signal strength versus distance for the defined work area. This reference table is stored in the memory module 28 of the reception subsystem 20. As the signal intensities of the directed beams are detected during operation of the navigation control system 10, the reception subsystem 20 uses the intensities of signal detected as pointers to the query table to determine the corresponding distances (between the reception subsystem 20 and the robotic device 100).

Alternatively, the reception subsystem 20 could be configured and operated to implement a signal processing algorithm that uses known attenuation properties, that is, the signal strength versus distance, of the operational frequency of the beams directed emitted by the 14n transmission units. This example assumes that the transmission units 14n are verified and emit directed beams of known signal strength.

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

For the sophisticated example of the navigation control system 10 described above, where the individual transmission units 14n of the transmission subsystem 12 operate at a single operating frequency, the detection units 30m of the reception subsystem 20 are configured to explore the set of unique operating frequencies used by 14n transmission units. The reception subsystem 20 is configured and operated so that the detection units 30M sequentially scan these frequencies during operation of the navigation control system 10.

For the example of the transmission subsystem 12 described above in relation to Figure 5A, Figure 5B illustrates the operating properties of the complementary receiving subsystem 20. The receiving subsystem 20 is configured and operated so as to detect the directed beams emitted during the predetermined synchronization period tSY. At the end of the predetermined synchronization period tSY, the reception subsystem 20 operates so that it starts the timing sequence tü. The receiving subsystem 20 operates so as to detect the directed beams as described herein. However, the reception subsystem 20 also operates so as to determine the time at which the maximum signal strength is detected, see the maximum reference character in Figure 5B. The reception subsystem 20 also operates so that it correlates the moment of detection of the maximum maximum signal intensity with the known instants in which the signal intensity of the directed beam emitted by each transmission unit 14n reaches its maximum, to identify the specific transmission unit 14n that transmitted the directed beam detected as having the maximum signal strength (for the descriptive example presented in Figures 5A, 5B, the third transmission unit 143).

For the example of the transmission subsystem 12 described above in relation to Figure 5C, Figure 5D illustrates the operating properties of the complementary receiving subsystem 20. The receiving subsystem 20 is configured and operated so as to detect the directed beams emitted during the predetermined synchronization period tsY. At the end of the predetermined synchronization period tsY, the reception subsystem 20 operates so that it starts the timing sequence t0. The receiving subsystem 20 operates so as to detect the directed beams as described herein (as illustrated, by way of example, by the detected signal pulses DP1, DP2, DP3, DP4 in Figure 5D). However, the reception subsystem 20 also operates so as to determine the two maximum signal intensities of the directed beams detected, see reference characters DP3 and DP2 in Figure 5D, which represent the two highest signal pulses detected, and the instants at which the two highest signal intensities were detected (t21 and t31 in Figure 5D).

The instants for detecting the signal strength allow the identification of the particular transmission units 14n in the robotic device 100, that is, the transmission units 143 and 142 in the example of Figure 5D. Next, the reception subsystem 20 also operates so as to calculate the ratio of amplitudes of these signal pulses, e.g. eg, DP3 / DP2, and use said calculated amplitude ratio as a pointer to a lookup table that identifies the angular orientation of the identified transmission units 143, 142, which in turn establishes the translation vector of the robotic device 100

Although the transmission units 14n mounted in combination with the robotic device 100 are interchangeable, the specific location of each individual transmission unit 14n in the robotic device 100 is a known quantity. Depending on the identification of the transmission unit 14n that emitted the directed beam detected by the reception subsystem 20, the reception subsystem 20 can perform quite simple geometric calculations, depending on the location of the identified transmission unit 14n, to determine the translation vector of the robotic device 100.

When the reception subsystem 20 functions as the base station, a means is required to communicate the

control signal to the robotic device. Consequently, some examples of the reception subsystem 20 which

It operates as a base station further including a transmission unit 32 (see Figure 3). Once the navigation control algorithm implemented by the microprocessor 24 has determined the prescribed behavior to be implemented by the robotic device 10, the microprocessor 24 operates so that it selects from the module of

memory 28 the appropriate control signal to implement said prescribed behavior. Then the

The microprocessor 24 operates so that it activates the transmission unit 32 to communicate (through its transmission) the control signal to the reception unit 16 of the robotic device 100, where the prescribed behavior defined by the control signal is implemented by means of the microprocessing unit 135.

Although the robotic device 100 is described (and depicted in FIG. 3) as being configured to include a dedicated receiving unit 16 for receiving control signals, transmitted by the transmitting unit 32 of the receiving unit 20, it is it is preferable that the omnidirectional detector 128 (of the virtual wall detection system) is adapted to detect and process said control signals. In those examples of the navigation control system 10 where the reception unit 20 is integrated in combination with the robotic device 10, the transmission unit 32 is not required. Instead, the reception unit 20 of the control system of Navigation 100 is electrically coupled to the microprocessing unit 135 (through an I / O port) of the robotic device 100, so that the receiving unit 20 can communicate control signals directly to the microprocessing unit 135.

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

As discussed above, in the examples of the navigation control system 10, the reception subsystem 20 functions as the base station, that is, the wall unit configuration, and the transmission subsystem 12 is integrated in combination with the robotic device 100. A preferred example, which is illustrative of the features and functionality of the navigation control system 10 according to the present invention, is illustrated by way of example in Figures 6A-6C.

Figure 6A depicts a robotic device 100 that operates in a defined work area WA, delimited by the walls W. A virtual wall unit VWU is located at the only entrance to the work area WA and operates so as to emit a beam of CB confinement, which confines the robotic device 100 to operations within the WA work area.

The transmission subsystem 12 of the illustrated example of the navigation control system 10 is integrated in combination with the robotic device 100 and comprises a set of transmission units 1 4n (eight (8) for the described embodiment, so that N is equal to the integers 1-8) that operate so that they generate a set of directed beams DBn (where N is equal to the integers 1-8), as illustrated in Figure 5B (in Figure 5B only two are illustrated directed beams DB3, DB4). The reference characters BA1 - BA8 identify the propagation axes of the directed beams DBn emitted by the transmission units 141-148, respectively. Each transmission unit 14n is configured and operated so that it emits a directed beam DBn having a predetermined emission pattern 0n, centered around the axis of the corresponding BAn beam. For the illustrated example, the emission pattern 0n of each directed beam DBn is approximately 100 °.

Preferably, the predetermined emission pattern 0n of the directed beams DBn is correlated with the number of transmission units 14n, so that the transmission subsystem 12 of the navigation control system 10 emulates an omnidirectional transmission source. An omnidirectional transmission source is necessary to ensure that the receiving subsystem 20 detects one or more directed beams DBn, since the position and orientation of the robotic device 100 in the defined work area (e.g., in terms of its movement forward FM), with respect to reception station 20, is an unknown variable at any particular time. Preferably, the emission patterns 0n of the directed beams DBn overlap.

As an examination of Figures 6A, 6B (and in particular of Figure 6B) shows, the directed beams DB3, DB4 emitted by the transmission units 143, 144, respectively, will be detected by the detection units 301, 302, 303 of the receiving subsystem 20. The detection units 301, 302, 303 operate so as to detect a parameter representative of the relative signal strengths of the detected beams DB3, DB4, p. eg, V1, V2, V3, respectively (as discussed above, each detection unit 30n operates so that it averages the signal intensities when two directed beams are detected simultaneously).

The reception subsystem 20 operates so as to implement the signal processing algorithm to calculate the absolute heading and distance between the reception subsystem 20 and the robotic device 100. Next, the reception subsystem 20 implements the control algorithm of navigation to correlate the calculated heading and distance with one of the cells comprising the crosslinked map of the defined work area WA stored in the memory module 28, and add said cell to the position history of the robotic device 100 to update the history of positions. Next, the reception subsystem 20 operates, according to the navigation control algorithm, so as to determine if there is a predetermined activation event associated with this updated position history. If there is, the reception subsystem 20 operates so that it selects the appropriate control signal, as determined by the navigation control algorithm, and transmits said control signal to the reception unit 16 of the robotic device 100 using the transmission system 32 (see figure 3). The microprocessing unit 135 of the robotic device 100 operates in response to the reception of the control signal by means of the omnidirectional detector 128, to implement the prescribed behavior, e.g. eg, one or more of the basic maneuvers and / or the behavior modes described by way of example herein, specified by the control signal.

In Fig. 7, an example implementation of the navigation control system 10 'according to the present invention is illustrated, where the transmission subsystem 12 functions as a base station and the reception subsystem 20 is integrated into combination with the robotic device 100. The transmission subsystem 12 comprises a distributed set of transmission units 14n positioned so that they are in contact with the walls W of the defined work area. As illustrated in Figure 7, the transmission subsystem 12 comprises a first transmission unit 141, a second transmission unit 142 and a third transmission unit 143 located in firm contact with the adjacent walls W, respectively.

Each transmission unit 14n comprising this distributed set is configured and operated so as to emit a directed beam having a predetermined emission pattern 0n along a predetermined beam axis DBn (DB1, DB2 and DB3 in Figure 7 define the predetermined beam axes for distributed transmission units 141, 142, 143, respectively) at a single operating frequency, preferably in the infrared frequency range and preferably modulated, as described herein. Preferably, each transmission unit 141, 142, 143 is configured and operated so as to generate a predetermined 0n beam emission pattern

5

10

fifteen

twenty

25

30

35

which effectively covers the defined work area WA, that is, 0n is approximately 180 ° for the distributed transmission subsystem 12 shown in Figure 7.

The reception subsystem 20 of the navigation control system 10 ′ preferably comprises a single omnidirectional detection unit 30, which may be of the type described in the US patent application. UU. pending resolution and joint ownership with serial number 10 / 056.804, filed on January 24, 2002, entitled METHOD AND SYSTEM FOR ROBOT LOCALIZATION AND CONFINEMENT (the virtual wall system is described in a summary way here). The omnidirectional detection unit 30 is configured and operated so as to explore the unique operating frequencies used by the distributed transmission units 141, 142, 143.

The omnidirectional detection unit 30 operates so as to detect the directed beams DB1, DB2, DB3 emitted by the distributed transmission units 141, 142, 143. The receiving subsystem is configured and operated so as to process the signals from the detected directed beam to determine the absolute position of the robotic device 100 within the defined work area WA. This absolute position is defined in terms of a reticulated map cell of the defined WA work area. A sequence of absolute positions, determined as described above, identifies a sequence of cells that defines the position history of the robotic device 100.

The reception subsystem 20 operates as described above to use a navigation control algorithm, in order to determine if an activation event has occurred in the position history, and if an activation event has occurred, the Receive subsystem 20 operates so that it communicates the control signal associated with the activation event / navigation control algorithm to the robotic device 100. The robotic device 100 operates, in response to the communicated control signal, so that it implements the prescribed behavior specified by the control signal.

According to the above principles, various modifications and variations of the present invention can be made. The navigation control system 10 has been described above as determining and using the instantaneous position (or a sequence of instantaneous positions) of a robotic device as a control parameter to directly alter the movement activity of the robotic device. Someone skilled in the art will appreciate that the navigation control system can be used for other purposes. For example, the navigation control system can be used to correct errors in the movement activity of robotic devices that depend on navigation by estimate. Therefore, it should be understood that, within the scope of the appended claims, the present invention can be practiced in a manner different from that specifically described herein.

Claims (10)

5 10 fifteen twenty 25 30 35 40 Four. Five fifty 55 60 1. A robotic cleaning device (100) comprising: a chassis (102) and an external frame (104) secured to the chassis (102) that defines a structural cover of a height that facilitates the movement of the robotic cleaning device below the furniture; left and right sets of main drive wheels (112L, 112R) and respective independent electric motors (11 4l, 114R), mounted independently in combination with the chassis (102) that moves with the permitted pivot, for a movement pivoting with respect to this at opposite ends of the transverse diameter of the chassis (102), and which can be moved between a retracted position, subject to the weight of the robotic cleaning device (100) during operation, and an extended position, where its axes of rotation are below the lower plane of the chassis; a navigation control system (10) that operates so as to monitor the movement activity of the robotic cleaning device (100) within a defined work area, where the monitored movement activity includes at least one of a position history of the robotic cleaning device and an instantaneous position of the robotic cleaning device (100); Y a transmission subsystem (12) that includes a laser transmitter, where the laser transmitter: is configured to redirect a transmission element of the laser transmitter; it is configured to cover the defined work area by transmitting a beam substantially parallel to a surface of the defined work area; Y it is integrated in combination with a raised point of a housing infrastructure of the robotic cleaning device (100), so that none of the structural characteristics of the robotic cleaning device (100) interferes with the operation of the transmission element of the laser transmitter, where the robotic cleaner further comprises a wheel drop sensor (124) integrated in combination with each of the main driving wheel assemblies (112L, 112R) and operating so as to generate a signal whenever any of the wheel assemblies Main drives (112L, 112R) are in an extended position. 2. The robotic cleaning device of claim 1, further comprising a receiving unit (16) configured to receive control signals. 3. The robotic cleaning device of claim 1 or claim 2, wherein the navigation control system (10) is configured to create a division of the work area defined by segmentation of the work area defined in a set of individual cells 4. The robotic cleaning device of claim 3, wherein the navigation control system (10) is configured to define a size of each individual cell, so that a dimension of length and width of each individual cell is not greater than one half of a width of a cleaning head system (145) of the robotic cleaning device (100). 5. The robotic cleaning device of any one of claims 1 to 4, further comprising a set of rechargeable batteries (110) which is integrated in combination with the chassis (102). 6. The robotic cleaning device of any one of claims 1 to 5, further comprising a front bumper (106) integrated in a movable combination with the chassis (102), wherein the front bumper (106) is configured so that when The robotic cleaning device (100) hits an obstacle, the bumper (106) moves to the chassis (102) and returns to an extended position when the contact with the obstacle ends. 7. The robotic cleaning device of any one of claims 1 to 6, further comprising an obstacle tracking unit (126) comprising an IR emitter-detector pair, configured to transmit a signal to a control module if an obstacle is detected as a result of the radiation reflected from the obstacle and detected by the detector. 8. The robotic cleaning device of any of claims 1 to 7, further comprising respective stop sensor units (130) integrated in combination with each respective respective and operational electric motor (114L, 114R), to transmit a signal to a control module when a change in the respective independent electric motor current (114L, 114R) is detected. 9. The robotic cleaning device of any of claims 1 to 8, further comprising at least one slope detection unit (122) comprising an IR emitter-detector pair, configured so as to transmit a signal to a module of control when a fall is found. 10. The robotic cleaning device of any one of claims 1 to 9, wherein the laser transmitter is configured so that it is sequentially activated / deactivated by cycles.